This invention is generally concerned with a mailing machine including jam detection structure, and more particularly with a mailing machine including low speed envelope feeding and jam detection structure.
As shown in U.S. patent application Ser. No. 07/783,594 for a Mailing Machine Including a Process For Selectively Moistening Envelopes Fed thereto, filed Oct. 28, 1991 by John R. Nobile, et. al. and assigned to the assignee of the present invention, there is disclosed a mailing machine including a microprocessor which is programmed for controlling separate motors for driving sheet feeding and postage printing structures, and which is programmed for controlling a solenoid, in response to operator input, for moving a baffle from a flap moistening position, wherein the baffle guides respective envelopes fed to the machine into engagement with flap deflecting structure for diverting an envelope flap toward flap moistening structure, to a non-flap moistening position, wherein the baffle guides such envelopes out of engagement with the flap deflecting structure. In order to compensate for the forgetfulness of an operator who uses the machine for moistening envelope flaps and does not return the baffle to the non-flap moistening position, with the result that sealed envelopes fed to the machine are torn by the flap deflecting structure, the '585 application provides structure for automatically returning the baffle, after a lapsed time interval, to the non-flap moistening position for guiding flaps out of engagement with the flap deflecting structure. As thus constructed and arranged, an operator need not be concerned with returning the machine to the non-flap moistening mode of operation after using the machine for moistening the flaps of a batch of envelopes. However, from time to tune an operator, in the course of feeding a batch of unsealed envelopes to the machine, inadvertently feeds a sealed envelope as well. And, since the baffle is positioned for guiding envelope flaps into engagement with the flap deflecting structure, the sealed envelope is torn, or if not torn, slowed down sufficiently to prevent the envelope from being properly located beneath the printing structure when printing occurs, with the result that postage is wasted. Accordingly:
an object of the invention is to provide a mailing machine which includes structure for detecting an envelope jam condition prior to printing an indicia thereon and aborting such printing in response to jam detection;
another object is to provide a mailing machine which includes structure for detecting sealed envelopes fed to the machine, when the machine is in an envelope flap moistening mode of operation, and aborting machine operation in response thereto;
another object is to provide a mailing machine including sheet feeding structure operable for feeding envelopes at a first speed for jam detection purposes and a second speed for postage indicia printing purposes; and
another object is to provide a mailing machine including structure for feeding a sheet in a path of travel and printing indicia thereon, with structure for discontinuing sheet feeding and printing if the sheet does not timely arrive at a predetermined position in the path of the travel.